year the light was brought into requisition. The triangulation commenced by observations between Divis mountain, near Belfast, and Slieve Snaght, the highest hill of Innishowen, a distance of sixty-seven miles. It was essential that a given point on Slieve Snaght should be observed from Divis, but though the work of observation was carried on from 23 Aug. to 26 Oct. the required point could not be sighted. Then the Drummond light was brought into play, with a result of which General Larcom has given a graphic account. Drummond's skill was also used in perfecting the Colby, or, as they are sometimes called, the Colby-Drummond compensation bars, by means of which the base of Lough Foyle—the most accurately measured base in the world according to Sir John Herschel—was measured [see Colby, Thomas Frederick]. In 1829 Drummond was engaged in rendering the limelight which he had discovered fit for lighthouse purposes. Experiments were tried to test its efficiency, and we have an account of the most important of these from an eye-witness. Several lights were exhibited from a temporary lighthouse at Purfleet in competition with the Drummond light, and Captain Basil Hall, who witnessed the exhibition, wrote to Drummond: ‘The fourth light was that which you have devised, and which, instead of the clumsy word “lime,” ought to bear the name of its discoverer. The Drummond light, then, the instant it was uncovered elicited a sort of shout of admiration from the whole party as being something much more brilliant than we had looked for. The light was not only more vivid and conspicuous, but was peculiarly remarkable from its exquisite whiteness. Indeed, there seems no great presumption in comparing its splendour to that of the sun, for I am not sure that the eye would be able to look at the disc of such light if its diameter were made to subtend half a degree.’
The superior brilliancy of the light having been established, the cost of production was very great, and Drummond was engaged in devising means for lessening the expense of manufacturing gas, management, &c., when in 1831 he glided into politics. In that year Drummond met Brougham at the house of a common friend, Mr. Bellenden Ker. An intimacy soon sprang up between them. Other political acquaintances were by degrees formed, Drummond's worth was quickly recognised, and when the time came for appointing the boundary commission in connection with the great Reform Bill Drummond was made head of the commission. For his services in connection with the commission a pension of 300l. a year was conferred on him, but with characteristic independence he declined after two years to accept it any longer. The business of the boundary commission over, Drummond's political friends resolved to keep him among them. In 1833 he became private secretary to Lord Althorp, then chancellor of the exchequer. In 1835 he was appointed under-secretary at Dublin Castle, and entered upon his great work of the administration of Ireland. Drummond arrived in Ireland at a critical moment in the history of the country. The Catholic Emancipation Act of 1829 had not brought contentment in its train, because the administration of the law continued one-sided and unjust. Admitted by law to political posts, catholics were excluded in fact; and all political power still remained in the hands of the protestant ascendency minority. Under these circumstances, O'Connell carried on an agitation for the repeal of the union from 1830 to 1835, and used his great influence in Ireland to thwart the executive and embarrass successive administrations. After the general election of 1835 O'Connell held the balance between the two great English parties, and finally threw his weight into the scale in favour of the whigs. With his aid the whigs, under Lord Melbourne, came into office, and a compact was practically made between the government and the Irish leader.
The basis of this compact—known as the Lichfield House compact—was that O'Connell should suspend the demand for repeal, and that the government should pass remedial measures for Ireland and administer the affairs of the country on principles of justice and equality. The Irish administration was nominally entrusted to Lord Mulgrave, the lord-lieutenant, and Lord Morpeth, the chief secretary, but Drummond was really in command.
He was practically the governor of the country, and for five years managed its affairs with wisdom, firmness, and justice, making the executive at once strong, popular, and efficient. Prior to his arrival Ireland was the scene of political agitation, social disorder, and religious feuds. The Orangemen, irritated and alarmed at the emancipation of the catholics, had formed an army of not less than two hundred thousand men to uphold the prerogatives of the dominant class. Orange processions and armed demonstrations terrorised Ulster and overshadowed the executive in Dublin. Catholic peasants struggled fiercely to overthrow the tithe system, and fought pitched battles with the military and police. The agrarian war raged with wonted fury, faction fights disgraced the land, and O'Connell loudly called for the
